Such devices are disclosed, for example, in S. L. Pastor et al. U.S. Pat. No. 3,208,682, N. J. Rosenburgh U.S. Pat. No. 3,467,340 and E. O. Wangerin U.S. Pat. No. 3,599,897. The cartridges to be handled by these devices were of various shapes.
In recent years, however, there is the tendency for cartridges to be generally in the same shape, i.e. in the form of a rectangular parallelepiped which is approximately square in section perpendicular to its film reel axis, in other words, which has four side faces of approximately identical rectangular shape surrounding the film face. The cartridges of such shape include those suited to the device of U.S. Pat. No. 3,208,682 mentioned above, those used for the Ectamate system of Eastman Kodak Co., and those adapted for use with the easy loading system of Minnesota Mining Manufacturing Co. These systems use very similar cartridges but differ in the arrangement for feeding out the microfilm, so that the cartridge specified for one system is not usable for another commonly.
We conducted intensive research in order to provide a device which is universally usable. Consequently, directing attention to the fact that cartridges, even if designed for different systems, have a film outlet approximately at the same position, we already proposed in U.S. patent application Ser. No. 253,461 a system having a film feed roller which is movable into the film outlet. The system is universally usable for any of cartridges to feed the film insofar as the cartridges are similary shaped and have a film outlet at the same location.
However, because various cartridges can be handled universally by the system and because the cartridges to be used have four side faces of the same rectangular shape, the system has the drawback that the user is likely to orient the cartridge improperly when loading it into the system. Even if the cartridge is thus misloaded, the misloading remains unnoticed until the system is actually operated. When the system misloaded with the cartridge is operated for feeding the film, the feeding mechanism and the cartridge will become damaged or have a shortened life.